The value of heart rate variability (HRV) in the fields of health, disease, and exercise science has been established through numerous investigations. The typical mobile-based HRV device simply records interbeat intervals, without differentiation between noise or arrythmia as can be done with an electrocardiogram (ECG). The intent of this report is to validate a new single channel ECG device, the Movesense Medical sensor, against a conventional 12 channel ECG. A heterogeneous group of 21 participants performed an incremental cycling ramp to failure with measurements of HRV, before (PRE), during (EX), and after (POST). Results showed excellent correlations between devices for linear indexes with Pearson’s r between 0.98 to 1.0 for meanRR, SDNN, RMSSD, and 0.95 to 0.97 for the non-linear index DFA a1 during PRE, EX, and POST. There was no significant difference in device specific meanRR during PRE and POST. Bland–Altman analysis showed high agreement between devices (PRE and POST: meanRR bias of 0.0 and 0.4 ms, LOA of 1.9 to −1.8 ms and 2.3 to −1.5; EX: meanRR bias of 11.2 to 6.0 ms; LOA of 29.8 to −7.4 ms during low intensity exercise and 8.5 to 3.5 ms during high intensity exercise). The Movesense Medical device can be used in lieu of a reference ECG for the calculation of HRV with the potential to differentiate noise from atrial fibrillation and represents a significant advance in both a HR and HRV recording device in a chest belt form factor for lab-based or remote field-application.

Over the past 10 years, smartwatches have become increasingly popular for commercial use. Their ever-increasing capabilities, accuracy, and sophistication of smartwatches is making them increasingly appealing to physical activity researchers as a valuable research tool. The non-invasive nature, prevalence, and versatility of smartwatches is being utilized to track heart rate, blood-oxygen levels, activity and movement, and sleep. However, the current state of the art lacks a uniform method to extract, organize, and analyze data collected from these devices. The objective of this research was to develop a Python software library that is widely available, highly capable, and easy to use with the data collected by the Apple Watch. The library was designed to offer data science, visualization, and mining features that help physical activity research find and communicate patterns in the Apple Health data. The custom-built caching system of the library provides near-instant runtime to parse and analyze large files without trading off on memory usage. The Wanjara Smartwatch Library has significantly better performance, proven reliability and robustness, and improved usability than the alternatives discovered in the review of the literature. / Master of Science / Over the past 10 years, smartwatches have become increasingly popular for commercial use. Their ever-increasing capabilities, accuracy, and sophistication of smartwatches is making them increasingly appealing to physical activity researchers as a valuable research tool. The non-invasive nature, prevalence, and versatility of smartwatches is being utilized to track heart rate, blood-oxygen levels, activity and movement, and sleep. However, the current state of the art lacks a uniform method to extract, organize, and analyze data collected from these devices. The objective of this research was to develop a Python software library that is widely available, highly capable, and easy to use with the data collected by the Apple Watch. The library was designed to offer data science, visualization, and mining features that help physical activity research find and communicate patterns in the Apple Health data. The custom-built caching system of the library provides near-instant runtime to parse and analyze large files without trading off on memory usage. The Wanjara Smartwatch Library has significantly better performance, proven reliability and robustness, and improved usability than the alternatives discovered in the review of the literature.

Thesis (M.S.)--University of Michigan, 1998. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 1998. / Includes bibliographical references.

Thesis (M.P.H.)--University of Texas Health Science Center at Houston, School of Public Health, 2008. / Source: Masters Abstracts International, Volume: 46-05, page: 2669. Adviser: R. Sue Day. Includes bibliographical references.

This thesis documents and explores health-related exercise (HRE) policy and practice within selected secondary schools in England and Wales, and examines the impact of the National Curriculum for Physical Education (NCPE) revisions (DfEE/QCA and Welsh Assembly, 1999) on the status and expression of HRE in the curriculum. It also considers the factors affecting teachers' approaches to change and their consequent decisions and behaviours. Specifically, the research makes comparisons between the policy and practice in schools at the time of data collection (2000) and that reported by Harris (1997). The methodology incorporated both qualitative and quantitative approaches. Case studies were completed in 2001 in five strategically selected mixed sex state schools, three of which were located in one Local Education Authority (LEA) in England and two of which were in one LEA in Wales. One of the English schools was a specialist sports college (SSC). Case study data analysis focused on the status and expression of health within each school, with particular attention to HRE policy and practice prior to and following the National Curriculum revisions. This analysis also explored the factors influencing the delivery of HRE in each department. The case study element of the research included the lesson observation of a unit of work on health-related aspects of PE in one school from the English LEA. This allowed an examination of the translation of school level policy into practice. A survey of all the secondary schools in the two case study LEAs in 2001 elicited questionnaire responses from 67.5% of heads of PE departments (PE HoDs). Analysis employed the Statistical Package for Social Scientists (SPSS). The findings revealed that delivery of HRE in case study schools was based on a fitness for sports performance perspective, utilising fitness testing and training. This was despite many teachers reporting a philosophy for physical education that reflected a fitness for life perspective with pupils adopting active lifestyles as its goal. Case study schools reported that the NCPE had influenced HRE delivery, however, limited change had resulted from the 1999 revisions.